Pathology of the thyroid gland

Question 1

hyperthyroidism: symptoms and signs

Answer 1

• hypermetabolism
• enhanced EPI effect
• lid lag - delay in downward movement of upper eyelid
• ATRIAL FIBRILLATION
• thyroid storm

Question 2

graves disease: pathophysiology

Answer 2

production of IgG antibody directed against TSH receptor called TSH receptor autoantibodies (TRAb)

Question 3

graves disease: thyroid hormone levels

Answer 3

high T3
high T4
low TSH

Question 4

patients presenting with myxedema must also present with what feature in order to have a diagnosis of HYPERthyroidism?

Answer 4

nodules

Question 5

hyperthyroidism: thyroid gland gross appearance

Answer 5

diffuse, symmetrical beefy red gland

Question 6

hyperthyroidism: histology

Answer 6

• hyperplastic follicles with papillary infoldings

- pale colloid with resportion vacuoles (“scalloping”)

Question 7

definition: myxedema

it is USUALLY associated with what thyroid disorder?

Answer 7

accumulation of hyrophilic ground substance (amorphous gel-like substance) throughout the CT of the body

hypothyroidism

Question 8

definition: cretinism

what are the distinctive features?

Answer 8

hypothyroidism presenting first in infancy or childhood

facial swelling 
puffy eyelids 
protruding tongue 
low hair line 
altered eyebrows

Question 9

screening for hypothyroidism must occur before what time period?

Answer 9

3rd week

Question 10

definition: hashimoto thyroiditis

Answer 10

chronic progressive thyroid disease - deficiency in Treg cells

increase in cytotoxic T cells and activated B cells

Question 11

pathogenesis: hashimoto thyroiditis

Answer 11

HLA Dr5 (check recording)

Question 12

gross appearance: hashimoto

Answer 12

diffusely enlarged

Question 13

histology: hashimoto

Answer 13

• mononuclear inflammatory infiltrates
• well developed germinal centers
• thyroid follicles are atrophic and are lined in many areas by epithelial cells distinguished by the presence of Hurthlecells

Question 14

Hurthle cells

Answer 14

• abundant eosinophilic granular cytoplasm

- metaplastic response of the normally low cuboidal follicular epithelial cells to ongoing injury

Question 15

de quervain thyroiditis: definition and symptoms

Answer 15

secondary to a viral infection by mumps, adenoviruses, echo, coxsackie

• painful 40-50 yo, F/M 4:1
• acute febrile onset with acute enlargement of the gland
• increased ESR
• transient increase in T3/T4 and decrease in TSH
• transient hyperthyroidism weeks to months self resolves

Question 16

de quervain thyroiditis: pathology

Answer 16

granulomas with giant cells, macrophages, lymphocytes, and destroyed thyroid follicles

Question 17

multinodular goiter: pathology

Answer 17

• colloid rich follicles of varying sizes with FLATTENED epithelium
• nodules, hemosiderin, hemorrhage, calcification

Question 18

thyroid tumors: cold nodules

Answer 18

palpable mass lesions that failr to take up radiolabeled iodine during nuclear scans

Question 19

thyroid tumors: hot nodules

Answer 19

palpable mass lesions that are hyperfunctioning and accumulate increased amounts of radioiodine relative to surrounding normal during scan

Question 20

thyroid adenoma

is it malignant or benign?

Answer 20

solitary, spherical encapsulated lesino that is demarcated from surrounding thyroid parenchyma by a well defined intact capsule

always benign, no chance to turn malignant

Question 21

thyroid cancer: tumor type prevalence and prognosis

Answer 21

papillary - 65% - great
follicular - 25% - 50/50
medullary - 5% - 50/50
anaplastic - 5% - high mortality

Question 22

papillary adenocarcinoma: gross appearance and histology

Answer 22

fibrovascular stalk with tumor cells

• orphan annie eye nuclei (marginated chromatin and optically clear centers - fixation artifact)
• psammoma bodies
• intranuclear cytoplasmic inclusion (INCI) aka nuclear hole
  nuclear grooves aka coffee bean nucleus

Question 23

follicular thyroid carcinoma

Answer 23

more aggressive

Question 24

medullary thyroid carcinoma

Answer 24

cancer of differentiating C cells

RET protooncogenes